[JS] get the search parameters of URL in hash mode

• Function encapsulation ：

function getHashSearchParam(key) {
    
  const url = location.href
  //  obtain  hash  value , It doesn't contain  '#'  Number 
  const hash = url.substring(url.indexOf("#") + 1)
  //  lookup  '?'  Index of number 
  const searchIndex = hash.indexOf("?")
  // '?'  Followed by the index parameter , If found, then +1, Remove '?'  Number 
  const search = searchIndex !== -1 ? hash.substring(searchIndex + 1) : ""
  //  Mention the search parameter string URLSearchParams Into object form 
  const usp = new URLSearchParams(search)
  //  adopt URLSearchParams Self contained get Method , The value corresponding to the query key 
  return usp.get(key)
}

• Use cases ：

//  Suppose the current page url by 
https://www.test.com/#/aa/bb?project_id=666

const project_id = getHashSearchParam("project_id")
console.log(project_id)		// '666'